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DTC P0118: ECT Sensor Input High: Testing

NOTE: Record freeze frame data. Check for service bulletins and on-line information.
  1. Connect scan tool to DLC-2. Turn ignition on. Check ECT V PID. If PID is more than 4.6 volts, go to next step. If PID is 4.6 volts or less, problem is intermittent. See TROUBLE SHOOTING - NO CODES article.
  2. Turn ignition off. Disconnect ECT sensor, located above starter. Check ECT sensor connector terminals. If connectors are okay, go to next step. If connectors are faulty, repair as necessary and go to step  8 .
  3. Connect a fused jumper wire between ECT harness connector terminals No. 1 and No. 2. See WIRING DIAGRAMS article. Check ECT V PID. If PID is not about zero volts, go to next step. If PID is about zero volts, replace ECT sensor and go to step  8 .
  4. Turn ignition on. Check voltage in White/Green wire between ground and ECT sensor harness connector terminal No. 1. If battery voltage is not present, go to next step. If battery voltage is present, repair short to power in White/Green wire between ground and ECT sensor harness connector terminal No. 1 and PCM harness connector terminal No. 38. See Figure . Go to step  8 .
  5. Turn ignition off. Disconnect PCM harness connector. PCM is mounted to passenger floor, behind glove box. Check connector terminals No. 38 and No. 91. If problem is not present, go to next step. If terminals are faulty, repair as necessary and go to step  8 .
  6. Connect breakout box to PCM harness connector. Leave PCM disconnected. Check continuity in Red/Blue wire between ECT sensor harness connector terminal No. 1 and breakout box terminal No. 38. If continuity is present, go to next step. If continuity is not present, repair open in Red/Blue wire. Go to step  8 .
  7. Check continuity in Brown/Green wire between ECT sensor harness connector terminal No. 2 and breakout box terminal No. 91. See WIRING DIAGRAMS article. If continuity is present, go to next step. If continuity is not present, repair open in Brown/Green wire between ECT sensor harness connector terminal No. 2 and PCM harness connector terminal No. 91. See Figure . Go to next step.
  8. Reconnect all components. Turn ignition on. Using scan tool, clear DTC. Start engine. Recheck DTCs. If DTC P0118 is present, replace PCM and go to next step. If DTC P0118 is not present, go to next step.
  9. Perform after repair procedure. See AFTER REPAIR PROCEDURE  . If DTC is not present, testing is complete. If any DTC is present, go to appropriate test for diagnosis and repair.
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